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I
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201
9
:
1
3
8
5
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1392
1386
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ce
s
s
u
p
p
o
r
ted
o
n
th
e
p
h
y
s
ical
m
ac
h
in
e
s
as
s
u
ch
m
u
s
t b
e
m
an
a
g
ed
s
u
c
h
t
h
at
o
n
e
u
s
er
d
o
n
o
t c
o
n
f
lict
w
it
h
a
n
o
th
e
r
u
s
er
i
n
r
elatio
n
to
th
e
s
h
ar
ed
r
eso
u
r
ce
s
allo
ca
te
d
to
th
e
m
.
T
h
e
r
eso
u
r
ce
s
t
h
a
t
ca
n
b
e
s
h
ar
ed
a
m
o
n
g
t
h
e
u
s
er
s
i
n
clu
d
e
v
ir
t
u
al
m
ac
h
in
e
s
,
s
to
r
ag
e,
m
e
m
o
r
y
,
n
et
w
o
r
k
b
a
n
d
w
id
th
etc.
T
h
e
ac
ce
s
s
ib
ilit
y
o
f
t
h
e
s
h
ar
a
b
le
r
eso
u
r
ce
s
a
m
o
n
g
s
ev
er
al
t
en
an
t
s
m
u
s
t
b
e
co
n
tr
o
lled
t
h
r
o
u
g
h
u
s
e
o
f
tech
n
iq
u
es
s
u
c
h
as
ac
ce
s
s
co
n
tr
o
l,
Vir
tu
al
s
to
r
ag
e
co
n
tr
o
ller
an
d
u
s
e
o
f
V
L
ANS.
C
lo
u
d
co
m
p
u
ti
n
g
s
y
s
te
m
s
also
ar
e
s
u
b
j
ec
ted
to
attac
k
s
w
h
ic
h
in
c
lu
d
e
s
id
e
ch
a
n
n
el
a
t
tack
,
b
r
u
te
f
o
r
cin
g
attac
k
,
n
et
w
o
r
k
p
r
o
b
in
g
etc.
,
f
r
o
m
w
h
ic
h
th
e
d
ata
an
d
t
h
e
a
p
p
licatio
n
s
m
u
s
t
b
e
p
r
o
tecte
d
.
T
h
e
m
o
s
t
i
m
p
o
r
ta
n
t
th
in
g
is
to
ac
h
iev
e
d
ata
is
o
latio
n
.
Mu
lti
-
te
n
an
c
y
is
a
n
i
m
p
o
r
tan
t
f
ea
tu
r
e
o
f
Saa
S
in
clo
u
d
co
m
p
u
ti
n
g
.
M
u
lti
-
te
n
a
n
ts
ca
n
s
h
ar
e
s
i
n
g
le
in
s
ta
n
ce
o
f
th
e
s
a
m
e
ap
p
licati
o
n
th
er
eb
y
s
h
ar
e
t
h
e
s
a
m
e
d
at
a
s
to
r
ag
e
ar
ea
.
Mu
lt
i
-
te
n
a
n
c
y
p
r
o
v
id
es th
e
u
s
er
t
h
e
ea
s
e
o
f
o
p
er
atio
n
s
an
d
r
ed
u
ce
s
d
eliv
er
y
co
s
t
f
o
r
a
h
u
g
e
n
u
m
b
er
o
f
te
n
an
ts
.
C
lo
u
d
co
m
p
u
ti
n
g
s
h
o
u
ld
s
u
p
p
o
r
t
I
s
o
latio
n
o
f
te
n
an
t
d
ata,
wo
r
k
s
p
ac
e
(
m
e
m
o
r
y
)
,
P
r
o
ce
s
s
ex
ec
u
tio
n
,
T
en
an
t
-
a
w
ar
e
s
e
cu
r
it
y
,
m
o
n
ito
r
in
g
,
m
an
a
g
e
m
e
n
t,
r
ep
o
r
tin
g
a
n
d
s
elf
-
s
er
v
ice
ad
m
in
is
tr
atio
n
,
I
s
o
latio
n
o
f
te
n
a
n
t
c
u
s
to
m
izatio
n
s
a
n
d
ex
te
n
s
io
n
s
to
b
u
s
i
n
ess
lo
g
ic,
ten
a
n
t
-
a
w
ar
e
v
er
s
io
n
co
n
tr
o
l,
T
en
an
t
-
a
w
ar
e
er
r
o
r
tr
ac
k
in
g
an
d
r
ec
o
v
er
y
etc.
s
o
as
to
en
s
u
r
e
th
at
t
h
e
d
ata
is
ac
tu
al
l
y
p
r
o
tect
ed
.
Mu
ltit
e
n
a
n
c
y
ca
n
b
e
ac
h
iev
ed
th
r
o
u
g
h
v
ar
io
u
s
m
o
d
els
th
at
i
n
clu
d
e
s
h
ar
ed
n
o
th
i
n
g
,
s
h
ar
ed
h
ar
d
w
ar
e,
s
h
ar
ed
OS,
s
h
ar
ed
d
atab
ase,
a
n
d
s
h
ar
ed
ev
er
y
t
h
in
g
.
Data
r
e
lated
to
m
a
n
y
u
s
er
s
co
u
ld
b
e
s
to
r
ed
in
t
h
e
s
a
m
e
d
atab
ase
an
d
m
an
a
g
ed
th
r
o
u
g
h
th
e
s
a
m
e
ap
p
licatio
n
th
at
h
a
s
b
ee
n
g
i
v
e
n
ac
ce
s
s
to
m
an
y
u
s
er
s
.
So
m
e
o
f
t
h
e
u
s
er
s
m
a
y
b
e
g
iv
e
n
ac
ce
s
s
to
th
e
s
a
m
e
tab
le
s
ex
i
s
ti
n
g
in
t
h
e
s
a
m
e
d
atab
ase.
T
h
e
u
s
er
s
f
o
r
th
e
s
a
m
e
ap
p
licatio
n
s
al
s
o
ar
e
g
iv
e
n
th
e
o
p
tio
n
o
f
co
n
f
i
g
u
r
i
n
g
t
h
e
ap
p
licatio
n
as
p
er
t
h
eir
b
u
s
in
e
s
s
r
eq
u
ir
e
m
e
n
ts
.
T
h
e
m
ai
n
i
s
s
u
e
i
n
th
e
ca
s
e
o
f
m
u
lt
i
-
te
n
an
c
y
is
th
e
d
ata
r
is
k
,
o
n
e
u
s
er
ta
m
p
er
i
n
g
th
e
d
ata
o
f
o
t
h
er
s
.
Mu
l
ti
-
ten
a
n
c
y
is
all
ab
o
u
t
is
o
lati
n
g
t
h
e
d
ata
in
s
u
c
h
a
w
a
y
t
h
at
t
h
e
o
w
n
e
r
o
f
t
h
e
d
ata
o
n
l
y
w
i
ll
h
a
v
e
a
cc
ess
a
n
d
k
ee
p
in
g
co
m
p
lete
co
n
f
id
en
tia
lit
y
.
Data
Ma
n
a
g
e
m
e
n
t
a
s
s
u
c
h
w
ill
b
e
th
e
k
e
y
is
s
u
e
k
ee
p
in
g
i
n
v
ie
w
o
f
co
n
f
id
en
t
ialit
y
an
d
p
r
iv
ac
y
o
f
th
e
d
ata.
Ma
n
y
r
u
le
s
an
d
r
eg
u
latio
n
s
m
u
s
t
b
e
in
-
b
u
ilt
i
n
to
clo
u
d
co
m
p
u
t
in
g
m
u
lti
-
te
n
a
n
c
y
en
v
ir
o
n
m
e
n
t
s
o
th
at
th
e
n
ee
d
s
an
d
th
e
r
e
g
u
lato
r
y
r
eq
u
ir
e
m
e
n
ts
o
f
d
if
f
er
e
n
t
u
s
er
s
ca
n
b
e
m
et.
Ne
v
er
th
ele
s
s
,
i
t
is
cr
itical
th
at
t
h
e
n
ee
d
to
s
eg
r
eg
ate
t
h
e
d
ata
an
d
p
r
o
v
id
e
d
p
r
o
p
er
ac
ce
s
s
co
n
tr
o
ls
s
o
th
at
n
o
u
n
au
th
o
r
ized
ac
ce
s
s
ca
n
b
e
g
ai
n
ed
.
Ma
n
y
C
h
alle
n
g
e
s
ar
e
to
b
e
m
et
w
h
e
n
o
n
e
i
m
p
le
m
en
ts
M
u
lti
-
T
en
an
c
y
.
E
n
d
u
s
er
s
r
eq
u
ir
es
P
er
f
o
r
m
a
n
ce
is
o
latio
n
,
A
v
ailab
ilit
y
o
f
all
th
e
r
eso
u
r
ce
s
,
Scalab
ilit
y
i
n
ter
m
s
o
f
ten
ets
r
eq
u
ir
e
m
en
ts
,
s
u
p
p
o
r
t
f
o
r
v
alu
e
ad
d
ed
ap
p
licatio
n
s
an
d
n
ee
d
f
o
r
p
r
iv
ac
y
an
d
s
ec
u
r
it
y
o
f
t
h
e
d
ata
ac
ce
s
s
ed
b
y
ap
p
licatio
n
s
,
ab
ili
t
y
to
cu
s
to
m
ize
t
h
e
ap
p
licatio
n
s
to
r
u
n
t
h
e
w
a
y
t
h
eir
ap
p
licati
o
n
s
ar
e
d
esi
g
n
ed
f
o
r
th
e
c
u
s
to
m
er
s
.
So
l
u
tio
n
d
ev
elo
p
er
s
ar
e
co
n
ce
r
n
ed
w
i
th
t
h
e
is
s
u
e
o
f
ac
ce
s
s
co
n
tr
o
l,
cu
s
to
m
izab
ilit
y
co
n
s
id
er
in
g
d
atab
ase,
B
u
s
in
e
s
s
lo
g
ic,
u
s
er
in
ter
f
ac
e,
w
o
r
k
f
lo
w
s
,
te
n
an
t
p
r
o
v
is
io
n
in
g
,
an
d
u
s
ag
e
b
a
s
ed
m
eter
i
n
g
.
Ser
v
ice
p
r
o
v
id
er
s
’
n
ee
d
s
to
d
ea
l
w
it
h
d
ata
s
h
ar
in
g
,
b
ac
k
u
p
,
a
n
d
r
esto
r
in
g
ten
a
n
t
d
ata,
en
h
a
n
ci
n
g
t
h
e
u
s
a
g
e
o
f
t
h
e
h
ar
d
w
ar
e,
r
ed
u
cin
g
t
h
e
o
p
er
atio
n
al
co
s
t,
d
ev
elo
p
m
en
t
o
f
h
u
m
an
r
eso
u
r
ce
s
,
r
ed
u
ce
th
e
d
ev
elo
p
m
en
t
ef
f
o
r
t,
r
ed
u
ce
th
e
ti
m
e
to
m
ar
k
et,
e
n
ab
le
m
en
t
o
f
th
e
m
u
tli
-
te
n
a
n
c
y
s
u
p
p
o
r
t
to
th
e
u
s
er
s
w
it
h
o
u
t
th
e
n
ee
d
to
m
a
k
e
an
y
co
d
e
ch
an
g
es.
M
u
lti
-
te
n
an
c
y
ca
n
b
e
i
m
p
le
m
e
n
ted
co
n
s
id
er
in
g
v
i
r
tu
aliza
tio
n
,
s
h
ar
i
n
g
o
p
er
atin
g
s
y
s
te
m
s
a
n
d
ap
p
licatio
n
s
.
Ma
n
y
m
eth
o
d
s
h
a
v
e
b
e
en
i
m
p
le
m
en
ted
to
ac
h
ie
v
e
m
u
lti
-
te
n
an
c
y
w
h
ic
h
in
cl
u
d
es
Vir
tu
al
izatio
n
,
d
ata
is
o
latio
n
,
an
d
m
a
n
ag
i
n
g
d
atab
ases
.
Vir
tu
aliza
t
io
n
is
cr
e
atin
g
m
o
r
e
lo
g
ical
m
ac
h
in
e
s
th
a
t
r
u
n
o
n
a
s
i
n
g
le
p
h
y
s
ical
m
ac
h
i
n
e
w
h
ich
i
s
co
n
n
ec
ted
w
it
h
m
o
r
e
n
u
m
b
er
o
f
r
eso
u
r
ce
s
an
d
also
th
at
m
an
y
o
p
er
atin
g
s
y
s
te
m
s
r
u
n
o
n
a
s
in
g
le
m
ac
h
in
e.
T
h
e
r
eso
u
r
ce
s
c
o
n
n
ec
ted
to
th
e
p
h
y
s
ica
l
m
ac
h
in
e
ar
e
s
h
a
r
ed
a
m
o
n
g
th
e
v
ir
tu
al
m
ac
h
in
e
s
.
A
co
n
f
i
g
u
r
ed
v
ir
tu
a
l
m
ac
h
i
n
e
c
an
o
p
t
to
r
u
n
a
s
p
ec
if
ic
o
p
er
atin
g
s
y
s
te
m
.
A
s
ep
ar
ate
v
ir
t
u
al
m
ac
h
i
n
e
ca
n
b
e
allo
ca
ted
to
ea
ch
o
f
t
h
e
te
n
a
n
t.
I
m
p
le
m
e
n
ti
n
g
v
ir
tu
aliza
ti
o
n
r
eq
u
ir
e
r
u
n
n
in
g
a
s
ep
ar
at
e
s
o
f
t
w
ar
e
s
u
ch
as
VM
w
ar
e
o
n
t
h
e
p
h
y
s
ical
m
ac
h
in
e.
T
h
e
s
o
f
t
w
ar
e
is
r
esp
o
n
s
i
b
le
f
o
r
p
r
o
v
id
in
g
s
er
v
ices
t
h
at
in
cl
u
d
e
s
ca
lab
ili
t
y
,
f
le
x
ib
ilit
y
,
r
eso
u
r
ce
s
h
ar
i
n
g
.
W
h
en
m
a
k
i
n
g
av
ailab
le
th
e
a
cc
ess
to
a
d
atab
ase,
v
ar
io
u
s
asp
ec
ts
h
a
v
e
to
b
e
s
u
p
p
o
r
ted
th
a
t
i
n
cl
u
d
e
s
ep
ar
atio
n
o
f
th
e
s
er
v
ices
p
r
o
v
id
e
d
to
d
if
f
er
e
n
t
te
n
a
n
ts
,
s
ca
li
n
g
t
h
e
ac
ce
s
s
to
t
h
e
d
atab
ases
b
ased
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2
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A
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Evaluation Warning : The document was created with Spire.PDF for Python.
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1387
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Data
b
ase
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Fig
u
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p
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[
3
]
,
[
2
]
.
T
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er
v
ices
i
m
p
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m
en
ted
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P
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al)
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h
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lead
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d
Vir
tu
al
la
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[
1
]
.
I
n
t
h
e
ca
s
e
o
f
M
u
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T
en
an
c
y
b
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t
h
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V
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d
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tack
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ap
p
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ca
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s
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attac
k
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ca
n
n
o
t
b
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m
i
tig
a
te
d
b
y
tr
ad
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m
eth
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as
t
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et
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o
d
s
ca
n
n
o
t p
en
etr
ate
in
to
th
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s
er
v
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s
.
T
h
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m
o
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i
to
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g
to
f
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d
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it
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t
h
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d
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ca
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ata.
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t
w
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h
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Vir
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Secu
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In
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
9
,
No
.
2
,
A
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201
9
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1
3
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1392
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s
u
c
h
c
a
n
n
o
t
p
r
o
tect
th
e
d
ata
th
a
t
is
attac
k
ed
w
it
h
i
n
t
h
e
p
u
r
v
ie
w
o
f
a
p
h
y
s
ical
m
ac
h
i
n
e.
Ma
n
y
is
s
u
es
ar
e
to
b
e
ad
d
r
ess
ed
w
h
en
d
ata
o
f
m
u
l
tip
le
u
s
er
s
i
s
s
to
r
ed
w
it
h
i
n
th
e
s
a
m
e
r
ep
o
s
ito
r
y
.
Me
c
h
an
i
s
m
s
ar
e
to
b
e
in
tr
o
d
u
ce
d
s
u
ch
t
h
at
th
e
d
ata
an
d
th
e
ap
p
licatio
n
ar
e
s
ec
u
r
ed
f
r
o
m
u
s
er
’
s
p
er
s
p
ec
ti
v
e.
A
l
s
o
th
er
e
e
x
is
t
s
a
n
o
p
p
o
r
tu
n
it
y
to
attac
k
t
h
e
d
ata
w
h
e
n
d
ata
is
r
etr
iev
ed
f
r
o
m
th
e
d
atab
ase
an
d
d
ec
r
y
p
ted
to
p
lai
n
t
ex
t
f
o
r
p
r
o
ce
s
s
in
g
.
T
h
e
p
r
o
ce
s
s
i
n
g
j
o
b
ca
n
b
e
in
ter
r
u
p
ted
to
ac
ce
s
s
t
h
e
p
lain
tex
t a
n
d
th
u
s
ca
n
b
e
attac
k
ed
.
T
h
er
e
s
h
o
u
ld
b
e
co
m
p
o
s
ite
a
n
d
co
m
p
lete
p
r
i
v
ac
y
an
d
s
ec
u
r
it
y
to
th
e
d
ata
o
f
m
u
l
tip
le
clien
t
s
s
to
r
ed
in
t
h
e
s
a
m
e
d
atab
ase
b
ein
g
ac
ce
s
s
ed
b
y
t
h
e
s
a
m
e
ap
p
licatio
n
w
h
ic
h
is
s
h
ar
ed
b
y
m
a
n
y
c
u
s
t
o
m
er
s
.
2.
RE
L
AT
E
D
WO
RK
T
h
e
m
ai
n
i
s
s
u
e
th
at
m
u
s
t
b
e
a
d
d
r
ess
ed
in
m
u
lt
i
-
te
n
an
c
y
is
t
o
allo
w
an
ap
p
licatio
n
to
b
e
ex
ec
u
ted
i
n
s
in
g
le
m
ac
h
in
e
w
h
er
e
it
h
as
to
b
e
co
n
n
ec
ted
to
a
s
i
n
g
le
d
ata
b
ase
w
h
ic
h
is
w
o
r
k
i
n
g
i
n
a
s
a
m
e
v
ir
tu
al
m
ac
h
i
n
e
s
o
th
at
w
e
ca
n
p
r
o
tect
th
e
ap
p
licatio
n
a
n
d
th
e
h
ar
d
w
ar
e
o
n
wh
ich
t
h
e
ap
p
licatio
n
i
s
d
ep
lo
y
e
d
as th
e
clie
n
ts
ar
e
allo
w
ed
to
s
h
ar
e
b
o
th
th
e
ele
m
en
ts
.
Mu
lti
-
ten
a
n
c
y
th
u
s
p
o
s
s
ess
e
s
m
a
n
y
c
h
alle
n
g
es
to
s
ec
u
r
e
an
d
p
r
eser
v
e
th
e
p
r
iv
ac
y
o
f
th
e
d
ata
o
w
n
ed
b
y
d
i
f
f
er
en
t
u
s
er
s
.
C
lo
u
d
co
m
p
u
tin
g
ar
ch
itect
u
r
e
m
u
s
t
i
n
cl
u
d
e
v
ar
io
u
s
is
s
u
es
r
elate
d
to
en
f
o
r
ce
m
e
n
t
o
f
th
e
s
ec
u
r
it
y
is
s
u
es.
T
h
e
v
er
y
f
ir
s
t
atte
m
p
t
to
i
n
cl
u
d
e
s
ec
u
r
it
y
i
n
to
clo
u
d
co
m
p
u
ti
n
g
in
f
r
astru
ct
u
r
e
w
a
s
at
te
m
p
ted
b
y
Ka
m
ar
a
et
a
l.
[
4
]
.
T
h
ey
h
a
v
e
co
v
er
ed
b
o
th
co
n
s
u
m
er
a
n
d
en
ter
p
r
is
e
s
ce
n
ar
io
s
an
d
th
e
y
h
a
v
e
u
s
ed
n
o
n
s
ta
n
d
ar
d
en
cr
y
p
tio
n
al
g
o
r
ith
m
s
s
u
c
h
a
s
s
ea
r
ch
ab
le
e
n
cr
y
p
tio
n
a
n
d
attr
ib
u
te
en
cr
y
p
tio
n
.
E
n
cr
y
p
tio
n
al
g
o
r
ith
m
s
ar
e
q
u
ite
f
r
eq
u
en
tl
y
e
m
p
lo
y
ed
to
s
ec
u
r
e
th
e
u
s
er
d
ata.
T
h
e
en
cr
y
p
tio
n
alg
o
r
ith
m
s
ca
n
b
e
u
s
ed
to
tr
an
s
f
o
r
m
t
h
e
u
s
er
s
’
cr
itical
d
ata
s
o
th
at
t
h
e
d
ata
ca
n
b
e
m
ad
e
to
b
e
in
-
ac
ce
s
s
ib
le
to
una
u
t
h
o
r
ized
u
s
er
s
ev
e
n
i
n
th
e
s
itu
atio
n
s
o
f
a
v
ailab
ilit
y
o
f
s
u
ch
d
ata
to
u
n
a
u
th
o
r
ized
u
s
er
s
.
An
alg
o
r
it
h
m
th
a
t
u
s
e
s
u
s
er
at
tr
ib
u
tes
a
n
d
t
h
eir
s
ig
n
a
tu
r
e
h
a
s
b
ee
n
p
r
esen
ted
b
y
Z
ar
an
d
io
o
n
et
a
l.
[
5
]
.
T
h
e
al
g
o
r
ith
m
is
in
cl
u
d
ed
in
to
a
p
r
o
to
co
l c
all
K2
C
(
Ke
y
to
C
lo
u
d
-
u
s
er
ce
n
tr
ic
p
r
iv
ac
y
p
r
eser
v
in
g
cr
y
p
to
g
r
ap
h
ic
ac
ce
s
s
co
n
tr
o
l p
r
o
to
co
l.
T
h
e
en
d
u
s
er
s
ca
n
s
ec
u
r
el
y
s
h
ar
e,
m
a
n
ag
e
a
n
d
s
to
r
es
th
eir
d
ata
in
th
e
clo
u
d
co
m
p
u
ti
n
g
i
n
f
r
astru
ct
u
r
e
w
h
ic
h
i
s
b
asicall
y
u
n
s
tr
u
ct
u
r
ed
.
Secu
r
i
t
y
o
f
th
e
d
ata
s
to
r
ed
o
n
th
e
clo
u
d
co
m
p
u
ti
n
g
s
y
s
te
m
ca
n
b
e
ac
h
iev
ed
th
r
o
u
g
h
i
m
p
le
m
en
t
in
g
ac
ce
s
s
co
n
tr
o
l
s
y
s
te
m
s
co
n
s
id
er
i
n
g
b
o
th
a
u
t
h
e
n
ticatio
n
an
d
au
th
o
r
izatio
n
s
;
t
h
e
y
h
a
v
e
p
r
esen
ted
a
m
ec
h
a
n
is
m
to
e
n
cr
y
p
t
t
h
e
d
ata
b
ased
o
n
t
h
e
lo
ca
tio
n
o
f
t
h
e
u
s
er
an
d
g
eo
lo
ca
tio
n
o
f
t
h
e
d
ata
w
h
er
e
it
h
a
s
b
ee
n
s
to
r
ed
.
Ma
n
y
m
e
th
o
d
s
h
a
v
e
b
ee
n
p
r
esen
ted
i
n
t
h
e
l
iter
atu
r
e
t
h
at
a
i
m
s
at
i
s
o
latin
g
d
ata
s
to
r
ag
e,
a
llo
ca
tin
g
s
ep
ar
ate
d
ata
s
to
r
ag
e
f
o
r
ea
ch
ten
an
t
etc.
[
6
]
E
ac
h
m
et
h
o
d
r
elea
s
es
a
d
if
f
er
en
t
s
ec
u
r
it
y
is
s
u
e
alto
g
et
h
er
th
a
t
in
v
o
l
v
es
u
s
e
o
f
d
if
f
er
en
t
t
y
p
e
s
o
f
en
cr
y
p
tio
n
tech
n
iq
u
e
s
.
An
attac
k
m
o
d
el
h
as
b
ee
n
p
r
esen
ted
w
h
ic
h
is
b
ased
o
n
a
th
r
ea
t
m
o
d
el
th
at
tak
es
ad
v
an
tag
e
o
f
M
u
lti
-
T
en
an
c
y
s
it
u
atio
n
is
p
r
esen
ted
b
y
[
3
]
.
Mitig
atin
g
th
e
attac
k
i
n
g
is
t
h
e
b
est
co
u
r
s
e
o
f
ac
tio
n
.
T
h
e
in
f
o
r
m
at
io
n
r
elat
ed
to
r
eso
u
r
ce
allo
ca
tio
n
,
r
eso
u
r
ce
u
tili
za
tio
n
a
n
d
ac
ce
s
s
i
n
g
ca
n
b
e
k
n
o
w
n
f
r
o
m
th
e
lo
g
s
m
ain
tain
ed
b
y
th
e
clo
u
d
s
.
T
h
e
s
ca
n
n
i
n
g
o
f
t
h
e
lo
g
s
an
d
ap
p
ly
i
n
g
b
r
u
te
f
o
r
ce
m
et
h
o
d
s
th
e
d
etails o
f
lo
ca
tio
n
s
w
h
er
e
d
ata
is
s
to
r
ed
co
u
ld
b
e
k
n
o
w
n
an
d
t
h
er
ef
o
r
e
ca
n
b
e
attac
k
ed
.
A
cc
e
s
s
co
n
tr
o
l
is
o
n
e
o
f
ap
p
r
o
ac
h
es
th
a
t
ca
n
b
e
e
n
f
o
r
ce
d
to
p
r
ev
en
t
u
n
a
u
t
h
o
r
is
ed
ac
ce
s
s
to
d
ata.
A
cc
e
s
s
co
n
tr
o
l
e
n
f
o
r
ce
d
f
o
r
co
n
tr
o
llin
g
th
e
ac
ce
s
s
w
h
ile
th
e
u
s
er
s
ar
e
i
n
m
u
lti
-
te
n
a
n
c
y
m
o
d
e
is
n
o
t
an
ef
f
ec
tiv
e
m
et
h
o
d
s
as
th
e
ac
ce
s
s
co
n
tr
o
l
is
m
er
el
y
ac
h
ie
v
ed
th
r
o
u
g
h
u
s
i
n
g
I
Ds
[
7
]
.
T
h
e
s
er
v
ice
p
r
o
v
id
er
ca
n
p
r
o
v
id
e
an
i
n
ter
f
ac
e
w
it
h
i
n
t
h
e
ap
p
licatio
n
u
s
i
n
g
w
h
ic
h
t
h
e
u
s
er
s
ca
n
co
n
f
i
g
u
r
e
t
h
e
ap
p
lic
atio
n
f
o
r
i
m
p
o
s
i
n
g
s
o
m
e
s
ec
u
r
it
y
co
n
s
tr
ain
t
s
.
T
h
e
s
ec
u
r
it
y
en
f
o
r
ce
m
e
n
t
ca
n
b
e
ex
ter
n
ali
s
ed
w
it
h
o
u
t
i
m
p
o
s
i
n
g
a
n
y
lo
ad
o
n
th
e
ap
p
licatio
n
Mo
h
a
m
ed
A
l
m
o
r
s
y
et.
al
[
8
]
.
Hav
e
p
r
esen
ted
a
co
m
p
ar
is
o
n
o
f
th
e
attr
ib
u
t
e
b
ased
en
cr
y
p
tio
n
(
A
E
S)
o
f
th
e
d
ata
to
b
e
s
to
r
e
d
in
th
e
clo
u
d
[
9
]
.
Ho
w
e
v
er
th
e
m
et
h
o
d
s
w
ill
b
e
d
ir
ec
ted
to
w
ar
d
s
ac
h
ie
v
i
n
g
th
e
ac
ce
s
s
co
n
tr
o
lli
n
g
o
f
th
e
d
ata
th
an
d
ea
lin
g
w
i
t
h
is
s
u
es
r
elate
d
to
m
u
l
ti
-
ten
a
n
c
y
.
[
1
0
]
Hav
e
s
h
o
w
n
t
h
e
k
in
d
o
f
is
s
u
es
t
h
at
m
u
s
t
b
e
ad
d
r
ess
ed
w
h
e
n
m
u
t
i
-
te
n
a
n
c
y
is
i
m
p
le
m
en
ted
in
I
aa
S
la
y
er
.
W
h
en
n
e
w
h
ar
d
w
ar
e
is
ad
d
ed
w
it
h
a
n
in
ten
t
io
n
o
f
i
n
cr
ea
s
i
n
g
th
e
p
er
f
o
r
m
an
ce
,
s
o
m
eti
m
e
s
it
lead
s
to
m
a
n
y
o
f
t
h
e
s
ec
u
r
it
y
is
s
u
e
s
as
w
ell.
T
h
e
au
th
o
r
s
h
av
e
p
r
ese
n
ted
a
m
o
d
el
u
s
in
g
w
h
ic
h
th
e
p
er
f
o
r
m
an
ce
o
f
a
clo
u
d
ca
n
b
e
co
m
p
u
ted
.
Data
I
s
o
latio
n
is
th
e
cr
itica
l
is
s
u
e
t
h
at
m
u
s
t
b
e
ad
d
r
ess
ed
w
h
e
n
it
co
m
e
s
to
m
u
lti
-
te
n
an
c
y
.
E
f
f
ec
ti
v
e
d
ata
m
a
n
a
g
e
m
en
t
s
y
s
te
m
s
m
u
s
t
b
e
i
m
p
le
m
en
ted
to
co
n
tr
o
l
th
e
ac
ce
s
s
to
t
h
e
d
ata
b
y
m
u
ltip
le
u
s
er
s
th
r
o
u
g
h
ac
ce
s
s
to
th
e
s
a
m
e
ap
p
licatio
n
.
A
p
p
r
o
p
r
iate
an
d
ex
ten
s
i
v
e
p
r
iv
ac
y
a
n
d
s
ec
u
r
it
y
to
th
e
d
ata
m
u
s
t
b
e
i
m
p
le
m
en
ted
.
T
h
e
p
u
b
lic
clo
u
d
s
as s
u
ch
ca
n
b
e
attac
k
ed
th
r
o
u
g
h
s
e
v
er
al
m
ea
n
s
as n
o
n
et
w
o
r
k
i
s
o
la
tio
n
is
i
m
p
le
m
e
n
ted
[
1
1
]
.
T
h
er
e
ar
e
m
a
n
y
p
r
o
b
lem
s
s
u
ch
a
s
r
ev
o
ca
tio
n
o
f
t
h
e
u
s
er
s
,
co
m
p
u
tat
io
n
al
ef
f
icie
n
c
y
,
h
i
er
ar
ch
ical
s
tr
u
ct
u
r
e
o
f
th
e
u
s
er
s
etc.
,
w
h
ich
ar
e
r
elate
d
to
s
ec
u
r
in
g
th
e
clo
u
d
s
to
r
ag
e
w
h
ile
attr
ib
u
t
e
b
ased
en
cr
y
p
tio
n
co
u
ld
s
o
lv
e
m
a
n
y
ac
ce
s
s
co
n
tr
o
l
r
elate
d
is
s
u
e
s
w
i
th
r
e
s
p
ec
t
to
clo
u
d
s
to
r
ag
e.
U
s
er
s
w
h
o
ar
e
attac
k
er
s
ca
n
lau
n
c
h
at
tack
s
o
n
co
-
r
esid
en
t
u
s
er
s
a
s
n
o
tr
af
f
ic
o
r
b
an
d
w
id
t
h
is
o
lat
io
n
i
s
i
m
p
le
m
e
n
ted
as
t
h
e
m
u
l
ti
-
ten
a
n
c
y
is
an
i
s
s
u
e
t
h
at
is
i
m
p
le
m
e
n
ted
w
it
h
i
n
a
s
i
n
g
le
s
er
v
er
[
1
2
]
.
DP
E
T
(
d
ata
P
ar
titi
o
n
en
cr
y
p
tio
n
tec
h
n
iq
u
es
is
o
n
e
s
u
c
h
m
et
h
o
d
)
[
2
]
.
I
n
t
h
is
m
et
h
o
d
ea
ch
r
ec
o
r
d
is
e
n
cr
y
p
ted
t
w
ice
b
ef
o
r
e
s
to
r
in
g
t
h
e
s
a
m
e
in
a
p
o
r
tio
n
th
at
is
allo
ca
ted
to
th
e
te
n
an
t.
E
n
t
ir
e
d
atab
ase
is
p
o
r
tio
n
ed
(
u
s
er
s
p
ac
e)
an
d
o
n
e
p
o
r
tio
n
i
s
allo
ca
t
ed
o
n
e
t
en
a
n
t
o
n
l
y
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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t J
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g
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SS
N:
2088
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8708
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ec
u
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g
Mu
lti
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ten
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cy
s
ystems
th
r
o
u
g
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m
u
lti DB
in
s
t
a
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ltip
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(
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1389
A
s
c
h
e
m
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is
u
s
ed
f
o
r
p
o
r
tio
n
in
g
a
n
d
allo
ca
tin
g
th
e
p
ar
titi
o
n
to
a
s
p
ec
if
ic
ten
an
t.
T
h
e
r
ec
o
r
d
is
en
cr
y
p
ted
u
s
i
n
g
a
p
u
b
lic
an
d
p
r
iv
ate
k
e
y
k
n
o
w
n
to
b
o
th
th
e
ten
a
n
t
an
d
C
SP
(
C
lo
u
d
s
er
v
ice
p
r
o
v
id
er
)
.
T
h
e
k
in
d
o
f
en
cr
y
p
tio
n
al
g
o
r
it
h
m
to
b
e
u
s
e
d
is
r
an
d
o
m
l
y
s
elec
ted
.
Firs
t
t
h
e
r
ec
o
r
d
is
en
cr
y
p
ted
b
y
te
n
a
n
t
u
s
i
n
g
p
u
b
lic
k
e
y
an
d
th
e
n
e
n
cr
y
p
ted
b
y
th
e
C
S
P
u
s
in
g
t
h
eir
o
w
n
p
u
b
lic
k
e
y
.
T
h
e
p
r
iv
ate
k
e
y
o
f
th
e
ten
a
n
t i
s
u
s
ed
at
t
h
e
ti
m
e
o
f
d
ec
r
y
p
tio
n
.
T
h
e
k
e
y
p
air
to
b
e
u
s
ed
f
o
r
ea
ch
o
f
th
e
ten
a
n
t
is
d
if
f
er
e
n
t
a
n
d
th
e
s
a
m
e
i
s
s
to
r
ed
in
th
e
d
ata
s
eg
m
e
n
t
r
elate
d
to
th
e
te
n
a
n
t
co
n
ce
r
n
ed
.
T
h
e
DE
PT
alg
o
r
ith
m
w
h
ile
p
r
o
v
id
es
ce
r
tai
n
lev
el
s
ec
u
r
it
y
,
t
h
e
d
ata
p
r
o
ce
s
s
ed
w
ith
in
t
h
e
s
er
v
er
ca
n
b
e
s
till
b
e
attac
k
ed
b
y
t
h
e
co
-
r
esid
en
t
u
s
er
s
d
u
e
to
l
ac
k
o
f
tr
af
f
ic
an
d
b
an
d
w
id
t
h
is
o
latio
n
.
Data
p
r
iv
ac
y
an
d
s
ec
u
r
it
y
o
f
t
h
e
d
ata
s
to
r
ed
in
clo
u
d
ca
n
b
e
ac
h
ie
v
ed
t
h
r
o
u
g
h
i
m
p
le
m
en
t
in
g
ac
ce
s
s
co
n
tr
o
l
m
ec
h
a
n
i
s
m
s
.
A
co
m
p
ar
is
o
n
o
f
cu
r
r
en
tl
y
ex
i
s
ti
n
g
A
E
S
-
B
as
ed
s
ch
e
m
e
s
o
f
d
ata
ac
ce
s
s
co
n
tr
o
l
h
a
s
b
ee
n
p
r
ese
n
ted
[
1
3
]
.
A
lis
t
o
f
u
n
s
o
lv
ed
p
r
o
b
lem
s
th
r
o
u
g
h
A
E
S
h
as
b
ee
n
e
n
lis
ted
.
E
v
e
n
th
o
u
g
h
t
h
e
A
E
S
b
ased
c
u
r
r
en
t
ex
i
s
ti
n
g
co
n
tr
o
l
s
ch
e
m
e
s
co
u
l
d
s
atis
f
y
t
h
e
r
eq
u
ir
e
m
e
n
ts
o
f
d
ata
ac
ce
s
s
co
n
tr
o
l
f
o
r
clo
u
d
s
to
r
ag
e,
th
er
e
ar
e
s
till
p
r
o
b
le
m
s
s
u
c
h
a
s
r
ev
o
ca
t
io
n
o
f
t
h
e
u
s
er
,
r
ed
u
ct
io
n
o
f
th
e
co
m
p
u
tatio
n
a
l
ef
f
o
r
t,
i
m
p
le
m
e
n
tatio
n
o
f
h
ier
ar
ch
ical
s
tr
u
ctu
r
e
o
f
t
h
e
u
s
er
etc.
Ma
n
j
in
d
er
Sin
g
h
et
a
l.
,
[
1
4
]
h
av
e
e
m
p
h
a
s
ized
th
at
o
n
e
h
a
s
to
en
s
u
r
e
d
ata
in
teg
r
i
t
y
to
th
e
clo
u
d
s
to
r
ag
e
th
r
o
u
g
h
u
s
e
o
f
d
i
f
f
er
en
t
d
ata
m
o
d
els
a
n
d
s
ec
u
r
it
y
alg
o
r
ith
m
s
.
T
h
e
y
h
a
v
e
p
r
esen
ted
a
n
ar
ch
itect
u
r
e
th
at
in
cl
u
d
es
th
e
s
ec
u
r
it
y
m
o
d
els
w
it
h
i
n
th
e
clo
u
d
co
m
p
u
ti
n
g
s
y
s
te
m
.
T
h
e
y
h
a
v
e
p
r
ese
n
te
d
a
m
o
d
i
f
ied
R
S
A
b
ased
alg
o
r
ith
m
t
h
at
h
as
b
ee
n
p
r
o
v
id
ed
w
it
h
a
d
i
f
f
er
e
n
t
k
e
y
g
e
n
er
atio
n
an
d
d
ec
r
y
p
tio
n
s
y
s
te
m
f
o
r
en
s
u
r
i
n
g
th
e
clo
u
d
s
to
r
ag
e
s
ec
u
r
it
y
.
An
a
n
al
y
s
is
o
f
d
ata
s
to
r
ag
e
in
clo
u
d
co
m
p
u
ti
n
g
an
d
t
h
e
k
i
n
d
o
f
s
ec
u
r
it
y
en
f
o
r
ce
m
en
t
t
h
at
ca
n
b
e
b
u
i
lt i
n
to
clo
u
d
co
m
p
u
ti
n
g
s
y
s
te
m
h
as b
ee
n
p
r
o
v
id
ed
[
7
]
.
T
h
ey
h
a
v
e
e
m
p
h
a
s
ized
th
a
t
th
e
m
ai
n
co
n
ce
p
t
is
to
p
r
o
v
id
e
in
teg
r
it
y
to
t
h
e
clo
u
d
s
to
r
ag
e
ar
ea
w
it
h
d
is
ti
n
ct
d
ata
m
o
d
el
s
an
d
s
ec
u
r
it
y
alg
o
r
ith
m
s
.
T
h
e
y
h
av
e
p
r
esen
ted
clo
u
d
d
ata
s
to
r
ag
e
ar
ch
ite
ctu
r
e
al
o
n
g
w
i
th
t
h
e
clo
u
d
d
at
a
m
o
d
els.
W
o
o
d
et
al,
[
1
5
]
h
av
e
p
r
esen
ted
s
er
ies
o
f
ch
al
len
g
es
th
a
t
o
n
e
m
u
s
t
f
ac
e
w
h
e
n
s
ec
u
r
it
y
to
t
h
e
clo
u
d
s
to
r
ag
e
h
a
s
to
b
e
en
s
u
r
ed
.
T
h
ey
h
a
v
e
co
n
ce
n
t
r
ated
m
ain
o
n
s
ec
u
r
i
n
g
th
e
clo
u
d
s
to
r
ag
e
co
n
s
id
er
i
n
g
th
e
m
u
lti
-
te
n
an
c
y
i
m
p
le
m
en
ted
th
r
o
u
g
h
Saa
S.
T
h
e
ch
allen
g
e
s
t
h
at
o
n
e
h
a
s
t
o
f
ac
e
i
n
p
r
o
v
id
in
g
th
e
s
ec
u
r
it
y
w
i
th
i
n
th
e
c
lo
u
d
co
m
p
u
ti
n
g
ar
e
p
r
ese
n
ted
in
d
e
tailed
b
y
Ka
tie
W
o
o
d
et
a
l.
,
[
8
]
.
T
h
ey
h
a
v
e
f
o
c
u
s
s
ed
s
p
ec
if
icall
y
ar
o
u
n
d
clo
u
d
d
ep
lo
y
m
en
t a
n
d
d
ata
s
to
r
ag
e,
i
n
p
ar
ticu
lar
r
elatio
n
to
p
r
iv
ac
y
co
n
ce
r
n
s
d
u
e
to
m
u
lt
i
-
ten
a
n
c
y
.
3.
I
NVE
ST
I
G
AT
I
O
NS A
N
D
F
I
NDIN
G
S
Ma
n
y
ap
p
r
o
ac
h
es
h
av
e
b
ee
n
p
r
esen
ted
i
n
t
h
e
l
iter
atu
r
e
f
o
r
s
ec
u
r
i
n
g
t
h
e
d
ata
i
n
a
s
in
g
le
d
atab
a
s
e
in
w
h
ic
h
t
h
e
d
ata
r
elate
d
to
d
if
f
er
en
t
cu
s
to
m
er
s
h
a
s
b
ee
n
s
to
r
ed
an
d
p
r
o
ce
s
s
ed
b
y
a
s
i
n
g
le
ap
p
licatio
n
.
All
t
h
e
ap
p
r
o
ac
h
es
u
s
ed
f
o
r
d
ea
lin
g
w
it
h
th
e
d
ata
s
u
f
f
er
f
r
o
m
o
n
e
k
i
n
d
o
f
r
i
s
k
ar
e
o
th
er
.
T
h
e
d
ata
s
to
r
ed
in
th
e
d
atab
ase
ca
n
b
e
d
o
u
b
le
en
c
r
y
p
ted
b
y
th
e
u
s
er
a
n
d
th
e
n
t
h
e
s
er
v
ice
p
r
o
v
id
er
s
o
as
to
g
u
ar
an
tee
th
e
co
n
f
id
e
n
tialit
y
f
r
o
m
b
o
th
p
er
s
p
ec
tiv
es.
T
h
en
i
n
t
h
at
ca
s
e
t
h
e
w
a
y
th
e
e
n
cr
y
p
tio
n
al
g
o
r
ith
m
s
ar
e
s
elec
ted
o
r
th
e
w
a
y
t
h
e
k
e
y
s
ar
e
g
en
er
a
ted
is
th
e
m
o
s
t
cr
u
cial
asp
e
ct
o
f
s
ec
u
r
i
n
g
t
h
e
d
ata
s
to
r
ed
in
th
e
d
atab
ase.
Data
is
o
latio
n
i
s
m
o
s
t
s
i
g
n
i
f
ic
an
t
a
s
p
ec
t
o
f
s
ec
u
r
in
g
th
e
d
ata.
T
h
e
d
ata
as
lo
n
g
as
it
is
in
s
i
n
g
le
d
atab
ase,
w
i
ll
b
e
in
s
ec
u
r
e
at
lea
s
t
at
p
h
y
s
ica
l
s
to
r
ag
e
lev
el.
P
h
y
s
ica
l
d
ata
is
o
latio
n
ca
n
b
e
d
o
n
e
b
y
d
is
tr
i
b
u
tin
g
t
h
e
d
ata
in
to
d
if
f
er
e
n
t
s
to
r
a
g
e
ar
ea
s
co
n
n
e
cted
to
d
if
f
er
en
t
p
h
y
s
ical
m
a
ch
in
e
s
.
T
h
e
d
atab
ase
is
as
s
ig
n
ed
to
p
h
y
s
ical
d
ata
s
to
r
ag
e
s
it
u
ated
i
n
d
i
f
f
er
e
n
t
m
ac
h
in
e
s
.
T
h
er
e
ar
e
m
an
y
tec
h
n
iq
u
e
s
th
a
t
ca
n
b
e
u
s
ed
to
s
e
g
r
eg
ate
th
e
d
ata
s
u
ch
th
at
v
er
y
h
i
g
h
le
v
el
o
f
d
ata
is
o
latio
n
ca
n
b
e
ac
h
iev
ed
.
B
o
th
th
e
ap
p
licatio
n
lev
el
an
d
d
ata
lev
el
is
o
latio
n
w
h
en
ac
h
iev
ed
w
i
ll
m
ak
e
t
h
e
e
n
tire
m
u
lti
-
te
n
an
c
y
s
y
s
te
m
to
b
e
f
u
ll
y
s
ec
u
r
ed
f
r
o
m
th
e
p
er
s
p
ec
ti
v
e
o
f
all
t
h
e
u
s
er
s
.
A
p
p
licatio
n
le
v
el
s
ec
u
r
it
y
ca
n
b
e
ac
h
iev
ed
th
r
o
u
g
h
s
u
i
n
g
s
ev
er
al
in
s
ta
n
ce
s
o
f
t
h
e
D
B
MS
s
o
f
t
w
ar
e
an
d
allo
ca
tio
n
ea
c
h
i
n
s
ta
n
ce
to
ea
ch
u
s
er
.
Ma
k
i
n
g
av
a
ilab
le
m
u
ltip
le
i
n
s
tan
ce
s
o
f
t
h
e
DB
M
S
s
o
f
t
w
ar
e
i
s
q
u
i
te
ex
p
en
s
iv
e
b
u
t
w
il
l
p
r
o
v
id
e
h
ig
h
le
v
el
o
f
s
ec
u
r
it
y
.
C
r
ea
t
in
g
s
e
v
er
al
d
atab
ases
ea
ch
o
p
er
ated
th
r
o
u
g
h
it
s
co
r
r
esp
o
n
d
in
g
DB
MS
in
s
tan
c
e
g
i
v
es
v
er
y
h
i
g
h
le
v
el
o
f
d
ata
is
o
latio
n
.
T
h
e
i
s
o
latio
n
le
v
el
w
il
l
f
u
r
t
h
er
i
n
cr
ea
s
e
w
h
e
n
th
e
d
atab
ases
ar
e
s
itu
a
ted
in
s
ev
er
al
p
h
y
s
ical
m
ac
h
in
es.
T
h
e
d
atab
ases
in
th
is
c
ase
ar
e
p
h
y
s
icall
y
d
is
tr
ib
u
ted
.
T
h
e
ar
r
an
g
e
m
e
n
t
o
f
m
u
ltip
le
i
n
s
ta
n
ce
o
f
DB
MS
s
o
f
t
w
ar
e
an
d
t
h
e
d
ata
is
s
h
o
w
n
in
t
h
e
Fi
g
u
r
e
2
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
9
,
No
.
2
,
A
p
r
il
201
9
:
1
3
8
5
-
1392
1390
Fig
u
r
e
2
.
Mu
lti
u
s
er
s
p
ac
es se
g
m
e
n
ted
d
atab
ase
w
o
r
k
i
n
g
u
n
d
er
SaaS
E
ac
h
o
f
th
e
d
atab
ases
i
s
r
ec
o
g
n
ized
b
y
th
e
I
P
Nu
m
b
er
o
f
P
h
y
s
ical
m
ac
h
in
e
s
o
n
w
h
ich
DB
is
cr
ea
ted
.
E
v
er
y
u
s
er
id
en
tifie
d
b
y
th
e
clo
u
d
co
m
p
u
tin
g
s
y
s
te
m
u
s
i
n
g
s
o
m
e
k
i
n
d
o
f
I
D
w
h
ich
is
ass
i
g
n
ed
b
y
clo
u
d
co
m
p
u
ti
n
g
s
y
s
te
m
.
W
h
e
n
a
u
s
er
m
a
k
es
a
r
eq
u
est
f
o
r
a
VM
to
r
u
n
a
SaaS
s
er
v
ice
th
e
h
y
p
e
r
v
is
o
r
s
h
all
m
ak
e
a
r
eq
u
est
to
th
e
ap
p
licatio
n
to
c
r
ea
te
a
d
atab
ase
o
n
d
if
f
er
en
t
s
er
v
er
o
n
w
h
ic
h
n
o
o
t
h
er
d
atab
ase
is
cr
ea
ted
.
T
h
e
ap
p
licatio
n
s
er
v
er
is
also
g
u
id
ed
to
cr
ea
te
a
s
p
ate
in
s
tan
ce
o
f
DB
MS
s
o
f
t
w
ar
e
an
d
th
e
n
atta
ch
a
n
e
w
l
y
cr
ea
ted
d
atab
ase
o
n
a
d
i
f
f
er
en
t
m
ac
h
in
e.
T
h
u
s
t
h
e
I
n
s
ta
n
ce
a
n
d
th
e
d
atab
ase
ar
e
b
in
d
ed
ti
g
h
tl
y
.
T
h
u
s
t
h
e
u
s
er
,
in
s
ta
n
ce
a
n
d
DB
ar
e
co
m
p
lete
l
y
i
n
ter
-
l
in
k
ed
ti
g
h
t
l
y
.
An
e
n
c
r
y
p
tio
n
al
g
o
r
ith
m
is
d
y
n
a
m
ica
ll
y
s
e
lecte
d
o
n
t
h
e
C
SP
s
id
e
b
ased
o
n
th
e
Na
m
e
o
f
th
e
i
n
s
tan
ce
a
n
d
th
e
I
P
ad
d
r
ess
o
f
t
h
e
p
h
y
s
ical
m
ac
h
i
n
e
o
n
w
h
ic
h
t
h
e
DB
is
cr
ea
ted
.
A
h
as
h
i
s
d
e
v
elo
p
ed
u
s
in
g
t
h
e
n
a
m
e
o
f
t
h
e
i
n
s
ta
n
ce
a
n
d
I
P
ad
d
r
ess
an
d
t
h
e
h
ash
is
i
n
d
ex
ed
in
to
en
cr
y
p
tio
n
al
g
o
r
it
h
m
u
s
in
g
a
l
o
o
k
u
p
t
ab
le.
Si
m
i
lar
l
y
,
o
n
t
h
e
User
s
id
e
an
al
g
o
r
ith
m
f
o
r
en
cr
y
p
tio
n
is
c
h
o
s
e
n
b
ased
o
n
eit
h
er
a
lo
o
k
u
p
tab
l
e
o
r
d
y
n
a
m
ical
l
y
s
elec
ted
b
as
ed
o
n
t
h
e
co
m
b
i
n
atio
n
o
f
p
u
b
lic
k
e
y
p
air
o
f
t
h
e
u
s
er
an
d
C
SP
.
T
h
e
m
et
h
o
d
is
b
ased
o
n
d
o
u
b
le
en
cr
y
p
tio
n
b
o
th
o
n
u
s
er
s
id
e
an
d
C
SP
s
i
d
e
an
d
th
e
d
ata
is
d
ec
r
y
p
ted
o
n
l
y
o
n
t
h
e
u
s
er
s
id
e.
T
h
e
k
e
y
an
d
t
h
e
en
cr
y
p
tio
n
alg
o
r
ith
m
ar
e
u
s
ed
to
en
cr
y
p
t t
h
e
d
ata
o
n
t
h
e
u
s
er
s
id
e
b
ef
o
r
e
it
is
tr
an
s
m
itted
to
th
e
VM
co
n
ce
r
n
ed
b
ased
o
n
th
e
lo
g
ical
p
o
r
t
n
u
m
b
er
p
r
o
v
id
ed
b
y
C
lo
u
d
co
m
p
u
ti
n
g
s
y
s
te
m
at
th
e
ti
m
e
o
f
r
eg
i
s
tr
atio
n
o
f
t
h
e
u
s
er
.
T
h
e
clo
u
d
co
m
p
u
ti
n
g
s
y
s
te
m
u
s
e
s
its
o
w
n
p
u
b
lic
k
e
y
an
d
t
h
e
e
n
cr
y
p
tio
n
al
g
o
r
it
h
m
s
elec
ted
b
ased
o
n
th
e
n
a
m
e
o
f
th
e
u
s
er
s
p
ac
e
a
n
d
e
n
cr
y
p
ts
t
h
e
d
ata
b
e
f
o
r
e
it
i
s
w
r
itte
n
to
t
h
e
co
n
ce
r
n
ed
u
s
er
s
p
ac
e.
T
h
ese
m
et
h
o
d
s
e
n
s
u
r
e
th
e
i
s
o
latio
n
a
t
t
h
e
ap
p
licat
io
n
lev
e
l
an
d
d
ata
lev
el.
W
it
h
in
th
e
A
p
p
licat
io
n
l
ev
el
a
t
h
r
ea
d
is
cr
ea
ted
f
o
r
ea
c
h
o
f
t
h
e
u
s
er
f
o
r
tr
an
s
p
o
r
ti
n
g
t
h
e
d
ata
eit
h
er
w
a
y
th
er
e
b
y
en
s
u
r
i
n
g
th
e
ap
p
lic
atio
n
la
y
er
i
s
o
latio
n
.
T
h
u
s
t
h
e
d
ata
p
r
o
tectio
n
is
i
m
p
le
m
en
ted
an
d
p
r
iv
ac
y
m
ai
n
tai
n
ed
o
n
b
o
th
th
e
e
n
d
s
o
f
th
e
cl
ien
t
a
n
d
C
SP
.
T
h
e
d
escr
ip
tio
n
o
f
th
e
d
ata
h
o
w
e
v
er
ca
n
b
e
u
n
d
er
ta
k
en
o
n
th
e
clie
n
t sid
e
u
s
i
n
g
t
h
e
p
r
iv
at
e
k
e
y
o
f
t
h
e
u
s
er
.
3
.
1
.
Alg
o
rit
h
m
I
n
itializatio
n
p
r
o
ce
s
s
1.
C
lie
n
t r
eq
u
est
f
o
r
an
in
s
ta
n
ce
an
d
a
d
atab
ase
is
s
en
t to
t
h
e
H
y
p
er
v
is
o
r
2.
T
h
e
ap
p
licatio
n
r
u
n
n
i
n
g
o
n
t
h
e
VM
w
ill
cr
ea
te
a
n
i
n
s
tan
ce
o
f
th
e
DB
MS,
lo
ca
tes
a
p
h
y
s
i
ca
l
m
ac
h
i
n
e
an
d
th
en
cr
ea
tes
t
h
e
Data
b
ase
o
n
t
h
e
ch
o
s
e
n
P
h
y
s
ica
l
m
ac
h
in
e.
A
b
o
n
d
in
g
i
s
estab
li
s
h
e
d
b
et
w
ee
n
th
e
A
p
p
licatio
n
,
DB
MS
i
n
s
tan
ce
a
n
d
th
e
Data
b
ase
3.
A
h
as
h
v
al
u
e
is
g
e
n
er
ated
b
ased
o
n
th
e
n
a
m
e
o
f
t
h
e
i
n
s
ta
n
c
e
an
d
th
e
I
P
n
u
m
b
er
o
f
th
e
p
h
y
s
ical
m
ac
h
i
n
e
o
n
w
h
ic
h
t
h
e
DB
is
cr
ea
ted
.
T
h
e
h
a
s
h
v
al
u
e
is
in
d
e
x
ed
in
to
t
h
e
k
i
n
d
o
f
E
n
cr
y
p
tio
n
alg
o
r
it
h
m
t
h
at
m
u
s
t b
e
u
s
ed
f
o
r
d
ata
en
cr
y
p
tio
n
o
n
th
e
C
SP
s
id
e.
A
d
if
f
er
en
t
e
n
cr
y
p
t
io
n
alg
o
r
it
h
m
i
s
s
elec
ted
ev
er
y
ti
m
e
h
as
h
in
d
ex
i
n
g
is
d
o
n
e.
4.
P
u
b
lic
k
e
y
p
air
g
e
n
er
atio
n
i
s
d
o
n
e
o
n
th
e
C
SP
s
id
e
an
d
th
e
p
u
b
lic
k
e
y
o
f
t
h
e
User
is
e
x
ch
a
n
g
ed
5.
T
h
e
u
s
er
I
D,
Ke
y
an
d
th
e
e
n
cr
y
p
t
io
n
al
g
o
r
ith
m
ar
e
s
to
r
ed
alo
n
g
w
it
h
u
s
er
I
D
w
ith
in
t
h
e
cl
o
u
d
D
B
M
S
In
s
t
a
n
c
e
-
1
D
B
M
S
-
In
s
t
a
n
c
e
-
2
D
B
M
S
-
In
s
t
a
n
c
e
-
3
D
B
M
S
–
In
s
t
a
n
c
e
-
4
A
p
p
l
i
c
a
t
i
o
n
DB
-
1
D
B
2
D
B
2
D
B
3
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2088
-
8708
S
ec
u
r
in
g
Mu
lti
-
ten
a
n
cy
s
ystems
th
r
o
u
g
h
m
u
lti DB
in
s
t
a
n
ce
s
a
n
d
mu
ltip
le
d
a
ta
b
a
s
es o
n
…
(
JKR
S
a
s
tr
y
)
1391
C
lie
n
t
-
s
id
e
p
r
o
ce
s
s
1.
T
en
an
t
‘
C
i’
g
e
n
er
ates
a
lar
g
e
P
r
im
e
C
p
f
r
o
m
h
is
o
w
n
cr
ed
e
n
tial
s
g
e
n
er
all
y
u
s
in
g
h
is
o
w
n
I
D
an
d
s
en
t
to
C
lo
u
d
Ser
v
ice
P
r
o
v
id
er
.
2.
T
en
an
t Ci
co
m
p
u
tes N=
2
*
C
p
3.
T
en
an
t Ci
g
e
n
er
ates
C
y
clic
g
r
o
u
p
Z
N
*
o
f
o
r
d
er
Ø(
N)
(
E
u
ler
Qu
o
tien
t
f
u
n
c
tio
n
)
4.
A
s
u
b
g
r
o
u
p
Z
Ø(
N)
*
s
u
b
s
et
o
f
Z
N
*
o
f
o
r
d
er
Ø(
Ø(
N)
)
is
g
en
e
r
ated
b
y
C
i
w
i
th
g
en
er
ato
r
g
∈
Z
n
*
5.
T
en
an
t
C
i
r
an
d
o
m
l
y
p
ic
k
s
u
p
t
w
o
p
r
i
v
ate
k
e
y
s
T
q
an
d
C
r
∈
Z
N
*
C
q
≡
g
k
1
m
o
d
N
a
n
d
C
r
≡
g
k
2
m
o
d
N
w
h
er
e
k
1
,
k
2
∈
Z
Ø(
N)
*
w
h
er
e
g
is
g
e
n
er
ato
r
f
o
r
Z
N
*
6.
T
en
an
t Ci
C
o
m
p
u
te
s
N=
C
q
*
C
r
C
i c
h
o
o
s
es
‘
e
’
s
u
ch
t
h
at
g
cd
(
e,
Ø(
N)
)
=1
C
i d
eter
m
i
n
es
‘
d
’
s
u
c
h
th
a
t e
d
≡
1
m
o
d
Ø(
N)
7.
T
en
an
t Ci
co
m
p
u
tes
C
P
r
=
e.
r
s
t su
ch
t
h
at
e.
r
s
t ≡
1
m
o
d
Ø(
N)
an
d
C
P
b
=d
.
r
s
d
s
u
ch
th
at
d
.
r
s
d
≡
1
m
o
d
w
h
er
e
C
P
r
: T
en
an
t P
r
iv
ate
Key
,
C
P
b
: T
en
an
t p
u
b
lic
k
e
y
P
u
b
lic
k
e
y
<N
,
C
P
b
>
P
r
iv
ate
k
e
y
<CP
r
,
d
,
e>
8.
T
en
an
t Ci
en
cr
y
p
ts
t
h
e
d
ata
o
f
ea
ch
r
ec
o
r
d
R
(
E
R
)
E
R
=
R
e
m
o
d
n
9.
T
en
an
t Ci
s
e
n
d
s
E
R
j
to
C
SP
to
s
to
r
e
in
th
e
d
atab
ase
P
i.
P
r
o
ce
s
s
in
g
o
n
t
h
e
C
lo
u
d
s
id
e
10.
C
SP
f
etc
h
es t
h
e
r
elate
d
E
n
cr
y
p
tio
n
alg
o
r
ith
m
a
n
d
th
e
k
e
y
with
t
h
e
h
elp
o
f
u
s
er
I
D
11.
C
SP
also
f
etc
h
es t
h
e
d
atab
ase
in
to
w
h
ic
h
t
h
e
d
ata
m
u
s
t b
e
wr
itten
12.
T
h
e
d
ata
r
ec
o
r
d
r
ec
eiv
ed
f
r
o
m
th
e
clien
t is e
n
cr
y
p
ted
ag
ai
n
u
s
in
g
t
h
e
k
e
y
an
d
en
cr
y
p
tio
n
al
g
o
r
ith
m
E
E
R
=
E
R
T
Pb
m
o
d
n
13.
C
SP
s
to
r
es E
R
i
n
u
s
er
s
p
ac
e
P
i o
f
C
i
Data
s
to
r
ag
e
R
etr
ie
v
al
p
r
o
ce
s
s
14.
T
en
an
t
en
cr
y
p
ts
th
e
P
r
i
m
ar
y
d
ata
u
s
in
g
h
i
s
o
w
n
k
e
y
a
n
d
al
g
o
r
ith
m
an
d
s
en
d
t
h
e
s
a
m
e
to
t
h
e
clo
u
d
a
lo
n
g
w
it
h
h
is
o
w
n
I
D
15.
C
SP
r
ec
eiv
es
th
e
p
r
i
m
ar
y
d
at
a
an
d
en
cr
y
p
t
s
th
e
s
a
m
e
u
s
in
g
th
e
k
e
y
an
d
d
y
n
a
m
icall
y
s
ele
cted
alg
o
r
ith
m
w
h
ic
h
is
co
n
n
ec
ted
w
it
h
th
e
i
n
s
tan
ce
n
a
m
e
an
d
lo
ca
tio
n
o
f
t
h
e
d
atab
ase.
16.
C
SP
f
etc
h
es
th
e
r
eq
u
e
s
ted
r
ec
o
r
d
f
r
o
m
th
e
r
elate
d
d
atab
ase
an
d
th
r
o
u
g
h
t
h
e
co
n
n
ec
ted
D
B
MS
in
s
ta
n
ce
u
s
i
n
g
en
cr
y
p
ted
p
r
i
m
ar
y
k
e
y
d
ata.
17.
T
h
e
q
u
er
ied
d
ata
is
s
en
t
to
t
h
e
clien
t.
I
t
s
h
o
u
ld
b
e
n
o
ted
t
h
at
n
o
d
ec
r
y
p
tio
n
is
d
o
n
e
o
n
t
h
e
clo
u
d
s
id
e.
Qu
er
y
i
n
g
is
d
o
n
e
u
s
i
n
g
t
h
e
e
n
cr
y
p
ted
k
e
y
v
alu
e
s
o
n
l
y.
18.
Af
ter
r
ec
eiv
i
n
g
T
en
an
t C
i c
o
m
p
u
tes R
=
E
E
R
r
s
t
m
o
d
N
to
o
b
tain
o
r
ig
i
n
al
R
ec
o
r
d
.
19.
I
f
T
en
an
t
C
i
d
o
es
n
o
t
g
et
R
ec
o
r
d
R
f
r
o
m
ab
o
v
e
d
ata
th
en
C
i
ass
u
m
es
R
is
m
o
d
if
ied
b
y
C
SP
o
r
in
tr
u
d
er
,
s
o
R
is
d
is
ca
r
d
ed
an
d
r
eq
u
ests
f
o
r
f
r
es
h
r
ec
o
r
d
.
4.
E
XP
E
R
I
M
E
NT
A
T
I
O
N
AN
D
R
E
SU
L
T
T
h
e
ab
o
v
e
m
en
t
io
n
alg
o
r
it
h
m
h
as
b
ee
n
i
m
p
le
m
e
n
ted
w
ith
in
th
e
E
u
ca
l
y
p
tu
s
an
d
ev
e
n
th
e
b
r
u
te
f
o
r
ce
m
et
h
o
d
ap
p
lied
to
ac
ce
s
s
t
h
e
d
ata
d
id
n
o
t
r
ev
ea
l
t
h
e
s
ec
r
ec
y
o
f
t
h
e
d
ata
s
to
r
ed
i
n
t
h
e
d
atab
ase.
I
t
h
a
s
n
o
t
b
ee
n
p
o
s
s
ib
le
to
ev
e
n
lo
ca
te
t
h
e
d
atab
ase
o
r
g
ain
h
a
n
d
le
o
n
t
h
e
alg
o
r
ith
m
a
n
d
t
h
e
k
e
y
u
s
ed
f
o
r
u
n
d
er
tak
i
n
g
th
e
en
cr
y
p
tio
n
o
n
th
e
C
SP
s
id
e.
5.
CO
NCLU
SI
O
N
W
h
en
ap
p
licatio
n
s
o
f
t
w
ar
e
th
at
u
s
es
a
d
atab
ase
h
as
to
b
e
p
r
o
v
id
ed
as
d
ata
s
er
v
ice
to
m
u
l
tip
le
u
s
er
s
th
r
o
u
g
h
v
ir
tu
a
l
m
ac
h
i
n
es,
th
e
is
s
u
e
o
f
Mu
lti
-
ten
a
n
c
y
ar
i
s
es.
T
h
e
d
ata
ca
n
b
e
attac
k
ed
b
y
th
e
u
s
er
s
d
u
e
to
th
e
r
ea
s
o
n
s
o
f
m
u
lti
-
te
n
an
c
y
.
On
e
u
s
er
ca
n
attac
k
o
t
h
er
as
b
o
th
th
e
u
s
er
s
ar
e
u
s
i
n
g
t
h
e
s
a
m
e
a
p
p
licatio
n
r
esid
en
t
o
n
th
e
s
a
m
e
s
er
v
er
.
T
h
er
ef
o
r
e,
it
b
ec
o
m
e
s
n
ec
ess
ar
y
t
o
i
m
p
le
m
en
t
m
e
th
o
d
s
/
Me
c
h
a
n
is
m
s
t
h
at
h
elp
i
n
p
r
o
tectin
g
t
h
e
d
ata
w
h
en
th
e
s
a
m
e
s
er
v
ices
ar
e
p
r
o
v
id
ed
to
s
ev
er
al
u
s
er
s
.
Data
is
o
lat
io
n
i
s
th
e
k
e
y
to
p
r
o
tect
th
e
d
ata
w
h
ich
ca
n
b
e
ac
h
iev
ed
th
r
o
u
g
h
cr
ea
ti
n
g
a
s
ep
ar
ate
d
atab
ase
o
n
a
d
if
f
er
en
t
p
h
y
s
ical
m
ac
h
i
n
e
t
h
u
s
ac
h
iev
in
g
b
o
o
th
lo
g
ical
an
d
p
h
y
s
ical
is
o
latio
n
.
T
h
e
ap
p
licat
io
n
lev
el
is
o
lat
io
n
is
ac
h
iev
ed
th
r
o
u
g
h
cr
ea
tio
n
o
f
m
u
ltip
le
d
atab
ase
in
s
ta
n
ce
s
.
T
h
e
m
et
h
o
d
is
ex
p
en
s
iv
e
t
h
at
m
o
r
e
n
u
m
b
er
o
f
DB
MS
in
s
ta
n
c
es
h
as
to
b
e
cr
ea
ted
an
d
m
o
r
e
n
u
m
b
er
o
f
p
h
y
s
ical
s
er
v
er
s
i
s
to
b
e
u
s
ed
f
o
r
lo
c
atin
g
t
h
e
d
atab
ases
.
Ho
w
e
v
er
,
th
e
m
et
h
o
d
is
f
u
l
l
p
r
o
v
es
th
at
it
s
ec
u
r
ed
th
e
d
ata
an
d
th
e
ap
p
licatio
n
1
0
0
%.
Do
u
b
le
en
cr
y
p
tio
n
b
y
b
o
th
th
e
u
s
er
an
d
C
SP
en
s
u
r
e
u
s
i
n
g
d
if
f
er
e
n
t
k
e
y
s
a
n
d
alg
o
r
ith
m
s
e
n
s
u
r
e
co
m
p
le
te
s
ec
r
ec
y
.
Dec
r
y
p
tio
n
is
d
o
n
e
t
h
e
u
s
er
s
id
e
o
n
l
y
r
ev
iv
i
n
g
co
m
p
u
tatio
n
al
o
v
er
h
ea
d
o
n
t
h
e
C
SP
s
id
e.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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8
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I
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t J
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&
C
o
m
p
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Vo
l.
9
,
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2
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A
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201
9
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1
3
8
5
-
1392
1392
RE
F
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R
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NC
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S
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.
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.
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u
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s
w
a
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u
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Ka
m
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